1. Field of the Invention
This invention relates to a sheet sorting apparatus, and more particularly to a sheet sorting apparatus provided with a sheet tray and adapted to sort sheets by pasting tags thereon.
2. Description of the Related Art
When sheets are printed out by an image processing apparatus, such as a facsimile transfer unit, a printer and a copier, sheets are discharged in order therefrom and stacked on one tray. During this time, when a sheaf of sheets are taken out from the tray after the printing of one document has finished, a problem does not arise, but, in some cases, sheets of a plurality of documents are discharged continuously and stacked on one tray. In such a case, when sheets are classified by documents and discharged, an end to a document is recognized conveniently on being taken out.
The sorting apparatuses adapted to have such an end to a document recognized include, for example, an offsetting function-carrying apparatus. In this apparatus, sheet discharge positions are staggered by documents. Owing to this arrangement, the positions in which the sheets are discharged are staggered little by little by sheets constituting the same document so that it comes to be understood that the portion of a sheaf of sheets at which a position is staggered shows an end to a document.
There is an apparatus having a function of inserting a ribbon between documents. In this apparatus, however, although a ribbon is placed on sheets discharged onto a tray, and subsequent sheets are discharged onto the ribbon, i.e., ribbons are inserted between the sheets, during the supplying of a ribbon, the discharging of sheets onto the tray is temporarily stopped, so that a ribbon inserting time is required, this causing the productivity to be lowered. Also, since such a ribbon is only held between sheets, there is the possibility that the ribbon falls off when a sheaf of sheets is taken out from the tray, and this causes a problem that a sorting position becomes indefinite.
There is also a method in which a plurality of trays are prepared so as to change trays whenever a document is discharged. This method causes an apparatus therefor to be enlarged, and the manufacturing cost to increase, and such an apparatus cannot be mounted on a small-sized machine.
Further, when sheets read continuously in an image scanner or reader are discharged, the same problems as mentioned above also arise.
Thus, the related art sheet sorting apparatuses have a low productivity, large dimensions and a high manufacturing cost, or a difficulty in carrying out a reliable sorting operation.